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By default, the per-user service file is named ~/.pg_service.conf . On Microsoft Windows, it is named %APPDATA%\\postgresql\\.pg_service.conf (where %APPDATA% refers to the Application Data subdirectory in the user's profile). A different file name can be specified by setting the environment variable PGSERVICEFILE . The system-wide file is named pg_service.conf . By default it is sought in the etc directory of the PostgreSQL installation (use pg_config --sysconfdir to identify this directory precisely). Another directory, but not a different file name, can be specified by setting the environment variable PGSYSCONFDIR .", "Connection parameters obtained from a service file are combined with parameters obtained from other sources. A service file setting overrides the corresponding environment variable, and in turn can be overridden by a value given directly in the connection string. For example, using the above service file, a connection string service=mydb port=5434 will use host somehost , port 5434 , user admin , and other parameters as set by environment variables or built-in defaults."]}, "comparison": {"left": "17", "right": "18", "status": "added", "diff": "--- PostgreSQL 17\n+++ PostgreSQL 18\n@@ -1 +1,8 @@\n-Not recorded in this version\n+{\n+  \"compiled_default_expression\": \"NULL\",\n+  \"default_evidence\": [],\n+  \"definition\": \"An OAuth 2.0 client identifier, as issued by the authorization server. If the PostgreSQL server requests an OAuth token for the connection (and if no custom OAuth hook is installed to provide one), then this parameter must be set; otherwise, the connection will fail.\",\n+  \"documented\": true,\n+  \"environment\": \"\",\n+  \"keyword\": \"oauth_client_id\"\n+}"}}